• Journal of the Korean Vacuum Society
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• v.14 no.2
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• pp.78-83
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• 2005

Nanometric crystalline silicon (no-Si) embedded in dielectric medium has been paid attention as an efficient light emitting center for more than a decade. In nc-Si, excitonic electron-hole pairs are considered to attribute to radiative recombination. However the surface defects surrounding no-Si is one of non-radiative decay paths competing with the radiative band edge transition, ultimately which makes the emission efficiency of no-Si very poor. In order to passivate those defects - dangling bonds in the $Si:SiO_2$ interface, hydrogen is usually utilized. The luminescence yield from no-Si is dramatically enhanced by defect termination. However due to relatively high mobility of hydrogen in a matrix, hydrogen-terminated no-Si may no longer sustain the enhancement effect on subsequent thermal processes. Therefore instead of easily reversible hydrogen, phosphorus was introduced by ion implantation, expecting to have the same enhancement effect and to be more resistive against succeeding thermal treatments. Samples were Prepared by 400 keV Si implantation with doses of $1\times10^{17}\;Si/cm^2$ and by multi-energy Phosphorus implantation to make relatively uniform phosphorus concentration in the region where implanted Si ions are distributed. Crystalline silicon was precipitated by annealing at $1,100^{\circ}C$ for 2 hours in Ar environment and subsequent annealing were performed for an hour in Ar at a few temperature stages up to $1,000^{\circ}C$ to show improved thermal resistance. Experimental data such as enhancement effect of PL yield, decay time, peak shift for the phosphorus implanted nc-Si are shown, and the possible mechanisms are discussed as well.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.665-676
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• 2003

To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.572-582
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• 2006

This survey was conducted from June 2004 to August 2004, through questionnaires given to 432 women aged ranging from 20 to 50 years, who were living in the Seoul metropolitan area. The questionnaires were designed to determine the physique, level of obesity and dieting survey as well as to uncover which diets were in fashion and their satisfaction degree. Dieting-related knowledge and dieting side effects were also investigated. The results were as follows: In dieting survey, as the age increased, dieting for health reason (52.3%) increased, whereas that for aesthetic reasons (32.6%) decreased (p<0.05). The most effective methods of dieting were exercise (50.2%) and diet (45.0%) regimens. In regards to exercise frequency, 46.5% for none, 23.5% for 1-2 times a week, suggesting that most respondents do not practice exercise for dieting purposes (p<0.05). Major source for dieting was shown to be obtained from relative family or friends (31.7%), newspapers or magazines (29.3%) and internet (14.9%). As the age decreased, information from the latter increased, whereas that from TV program (21.2%) decreased (p<0.05). Reasons for excess weight were bad eating habits (39.6%), lack of exercise (38.3%), pregnancy and childbirth (10.6%). In fad dieting, while organic foods and aerobic exercises scored the highest satisfaction degree among diet and exercise regimens, on the other hand, sauna, steam baths and high temperature half-immersion baths scored the highest among surgery and other special therapies. As the age increased, the satisfaction degree for organic foods such as organic vegetable and high functional boiled cooked rice increased (p<0.05). As the age increased, scores on dieting-related knowledge decreased. Side effects of dieting included dizziness 06.2%) fatigue (15.1%) indigestion/constipation (11.1%) physical weakness 00.5%), loss of concentration (7.8%), dry skin (7.4%) loss of motivation (6.7%). The above results showed that attitude toward dieting among adult women varied with age and in light of the well-being trend, organic foods and aerobic exercises scored the highest satisfaction degree through all age.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.3
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• pp.71-83
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• 2018

Recently, there are many efforts to define the field of entrepreneurship as an area of independent study. According to Shane & Venkataraman, the study of entrepreneurship is moving toward understanding the combination of entrepreneurial individual and valuable opportunity in becoming entrepreneurs. In Korea, entrepreneurship education is spreading widely on the basis of universities and in 2010 the entrepreneurship major was created in Sookmyung Women's University for the first time in Korea. The results of this study are as follows. First, there are many research about examining the relationship between entrepreneurship education and entrepreneurship intention. Nevertheless, there are lack of the study focusing on the opportunity recognition which many scholars have recognized as the independent study field of entrepreneurship domain. Therefore, the purpose of this study is to examine the effect of satisfaction of entrepreneurship major education on entrepreneurial opportunity recognition and to examine the mediating effect of entrepreneurial opportunity recognition according to educational commitment. The questionnaires were carried out for 3 weeks to entrepreneurship major students in Sookmyung Woment's University. A total of 84 surveys were collected and statistically analyzed by the R program. As a result of the analysis, it was found that the satisfaction of education positively influences the recognition of entrepreneurial opportunities. Commitment also has a full mediating effect on the recognition of entrepreneurial opportunities. The results of this analysis confirm that the ability to recognize entrepreneurial opportunity is developed by entrepreneurship education, and during the study students' commitment has an important role in the relationship between educational satisfaction and entrepreneurial opportunity recognition. The results were verified through empirical analysis. Satisfaction with entrepreneurship education and awareness of entrepreneurship opportunities through entrepreneurship can be anticipated as entrepreneurship activities in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.452-457
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• 2009

The objective of this study was to provide fundamental data on breeding cultivar and cultural technique to identify quality characterization according to damage degrees in rice when are damaged at low temperature. For induction of cold damage, we treated the irrigation water at $17^{\circ}C$ from the panicle formation stage to the heading date. The rice products were harvested by grades according to the sterility ratio and investigated 5 items of quality analysis including ripened grain ratio, brown/rough rice ratio, 1000 grain weight of brown rice, protein content, and amylose content. The quality analysis were characterized by each items according to the sterility ratio. As a result, the ripened grain ratio was y=1.0444x-7.6597($R^2=0.9874^{**}$), protein content was y=-0.046x+10.875 ($R^2=0.6973^*$), and head rice ratio was y=-0.2306x+104.32 ($R^2=0.634^*$), but the amylose content, brown/rough rice ratio and the milled/brown rice ratio were not significant. The rice plants, which injured by the low temperature, had bad influence in the yield and quality. Consequently, the breeding of rice cultivar and development of cultural technique are required to improve its cold tolerance.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.226-234
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• 1984

In order ti find out the optimum seeding time(OST) and optimum seed rate(OSR) of Italian ryegrass on seed production, this studies with tetraploid cv. Tetrone were carried out on the experimental field of Livestock Experiment Station. Treatments included seed rates of 1, 2, 3 and 4 kg per 10a and combined with seeding time on 20, 30 Aug, 9, 19 and 29, September 1983. Seeds were sown in rows 50 cm apart and were spaced in a continuous line with width of 15 cm within the rows. The results are summarized as follows: 1. Autumn tillers could be classified into three groups from winter-killing point of view, namely winter-killing completely, damaged growing point only and living tillers. 2. The young inflorescence-bearing stem in Italian ryegrass which were sown earlier than 9. September were more susceptible to winter killing. Tiller buds in those stems which originated from an axillary buds at the stem base within senescent leaf-sheaths emerged lately in spring, and consequently heading was delayed, culm length shortened and seed yield reduced. 3. Tiller buds which originated from damaged growing point only and living tillers in moderate shoots emerged early in spring and those tillers became mainly spike-bearing culm. 4. The emergence-time of tillers influenced on culm-, spike- length and ripenness more than seeding time and seed rate. 5. Seed yield was mostly affected by the number of spikes per unit area. 6. For the safety of over-wintering and enough spikes on seed production, OST and OSR at Suweon were the last part of September and 2-3 kg per 10a, respectively. Especially OSR was 2 kg per 10a for early and 3 kg per 10a for late OST.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.409-425
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• 2018

Occurrence and yield characteristics of lepidopteran insect pests in both PUR (paddy-upland rotation) and CU (continuing upland) fields for 8 maize (Eolrukchal 1, Heugjeom 2, Miheukchal, Ilmichal, Heukjinjuchal, Chalok 4, Mibaek 2, Daehakchal) and 7 sorghum (Hwanggeumchal, Anzunbaengisusu, Moktaksusu, Sodamchal, DS-202, Nampungchal, Donganme) varieties was surveyed. The population of Ostrinia furnacalis adults showed 3 times highest peaks in 2016. In addition, the damaged ratios of maize and sorghum leaves and stems were increased depending on the growth periods of the crops and those by O. furnacalis larvae were also increased steeply in mid August. The damaged ratios of maizes such as Miheukchal, Eolrukchal 1, Ilmichal, Heugjeom 2, and Mibaek 2 by O. furnacalis larvae were statistically different (P=0.05) between organically managed PUR and CU fields. Except for DS202 among sorghum varieties, the damaged ratios of the other ones were high and similar (50-92%) in the CU field. The ear damaged ratio of maize varieties by lepidopteran larvae including O. furnacalis and Helicoverpa armigera was from 5 to 38% in Chalok 4 and Heukjinjuchal, respectively, and Daehakchal gave relatively higher damage ratio in the PUR field (33%) than in the CU field (14%). The ear ratio of Sodamchal and DS-202 varieties in the PUR field was 94 and 82%, and all sorghum varieties were damaged over 78% by lepidopteran larvae in the CU field. Interestingly, the correlation coefficients between the damaged ratio and invasive pores on their stems by O. furnacalis larvae were positive (maize $r=0.69_{paddy-upland}$, $0.95_{continuing}$; sorghum $r=0.93_{paddy-upland}$, $0.97_{continuing}$, respectively). Additionally, the correlation coefficients between the damaged ratio and the ear weight or the thousand kernel weight (g) of maizes and sorghums by lepidopteran larvae were negative (maize $r=-0.38_{paddy-upland}$, $-0.49_{continuing}$; sorghum $r=-0.70_{paddy-upland}$, $-0.57_{continuing}$, respectively). These results indicate that the focused management on lepidopteran insect pests occurring maizes and sorghums cultivated in PUR and CU fields is an important strategy to secure their yields.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.341-350
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• 2009

The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of $10^6\;CFU$, $10^7\;CFU$, $2{\times}10^7\;CFU$, $10^8\;CFU$ of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed $1^{st}$ week, $2^{nd}$, $3^{rd}$ and $4^{th}$ weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries.

• Journal of Plant Biotechnology
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• v.39 no.1
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• pp.33-48
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• 2012

As a scientific curiosity to understand the structure and the function of crops and experimental efforts to apply it to plant breeding, genetic maps have been constructed in various crops. Especially, in the case of Brassica crop, genetic mapping has been accelerated since genetic information of model plant $Arabidopsis$ was available. As a result, the whole $B.$ $rapa$ genome (A genome) sequencing has recently been done. The genome sequences offer opportunities to develop molecular markers for genetic analysis in $Brassica$ crops. RFLP markers are widely used as the basis for genetic map construction, but detection system is inefficiency. The technical efficiency and analysis speed of the PCR-based markers become more preferable for many form of $Brassica$ genome study. The massive sequence informative markers such as SSR, SNP and InDels are also available to increase the density of markers for high-resolution genetic analysis. The high density maps are invaluable resources for QTLs analysis, marker assisted selection (MAS), map-based cloning and comparative analysis within $Brassica$ as well as related crop species. Additionally, the advents of new technology, next-generation technique, have served as a momentum for molecular breeding. Here we summarize genetic and genomic resources and suggest their applications for the molecular breeding in $Brassica$ crop.

• Korean Journal of Remote Sensing
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• v.30 no.1
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• pp.83-107
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• 2014

This study presents spatial characteristics of cloud using satellite image in the extreme heavy snowfall of the Yeongdong region. 3 extreme heavy snowfall events in the Yeongdong region during the recent 12 years (2001 ~ 2012) are selected for which the fresh snow cover exceed 50 cm/day. Spatial characteristics (minimum brightness temperature; Tmin, cloud size, center of cloud-cell) of cloud are analyzed by tracking main cloud-cell related with these events. These characteristics are compared with radar precipitation in the Yeongdong region to investigate relationship between cloud and precipitation. The results are summarized as follows, selected extreme heavy snowfall events are associated with the isolated, well-developed, and small-scale convective cloud which is developing over the Yeongdong region or moving from over East Korea Bay to the Yeongdong region. During the period of main precipitation, cloud-cell Tmin is low ($-40{\sim}-50^{\circ}C$) and cloud area is small (17,000 ~ 40,000 $km^2$). Precipitation area (${\geq}$ 0.5 mm/hr) from radar also shows small and isolated shape (4,000 ~ 8,000 $km^2$). The locations of the cloud and precipitation are similar, but in there centers are located closely to the coast of the Yeongdong region. In all events the extreme heavy snowfall occur in the period a developed cloud-cell was moving into the coastal waters of the Yeongdong. However, it was found that developing stage of cloud and precipitation are not well matched each other in one of 3 events. Water vapor image shows that cloud-cell is developed on the northern edge of the dry(dark) region. Therefore, at the result analyzed from cloud and precipitation, selected extreme heavy snowfall events are associated with small-scale secondary cyclone or vortex, not explosive polar low. Detection and tracking small-scale cloud-cell in the real-time forecasting of the Yeongdong extreme heavy snowfall is important.